It's led me to a few conclusions/thoughts.
1 - Eagles have a higher than average will to live.
2 - It's good my transmission shifts smooth - a couple hard shifts and that would be all she wrote.
3 - A lot of the original AMC components are really good quality. The biggest thing that surprised me during the replacement process is that I still have the original starter, or at least it's an original American Motors starter. 172k and 25 years old, not bad.
4 - It's probably easier to take the trans and tc out to replace the flex plate. We did it on a lift, and just slid everything back. It took about an hour of screwing around and dropping pieces to get the first bolt started in the new plate. And it seemed dangerous to have that massive hunk of metal supported by 2x4's and pieces of angle iron on jacks with nothing holding it securely, while standing underneath it. It took 3 of us 9 hours with no breaks.